code: def _add_verbose_flag(parser):
      parser.add_option(
          "--verbose",
          dest="verbose",
          help="Enable verbose mode (printing of log messages).",
          default=None,
          action="store_true",
      )
  
file_path: mne-python/mne/commands/utils.py
imports: import glob
  import importlib
  import os
  import os.path
  import sys
  from optparse import OptionParser
  import mne
label_desc: Use image node_id 1 for calling a global function with example usage: _add_verbose_flag(parser) without return types